Diaphragm valve



July 31, 1951 L. A. KEMP'roN 2,562,315

DIAPHRAGM VALVE Filed JuneA 29, 1946 INVENTOR. zu /f KEMP ro/v Patented `luly 31, 1951 DIAPHBAGM VALVE Leslie A. Kempton, Chicago, lll., assignor to The Dole Valve Company, Chicago, lll., a corporation of New York Application June 29, 1946, Serial No. 680,421

4 Claims. (Cl. 137-139) This invention relates to a diaphragm valve andmore particularly, to a diaphragm valve oi.' the so-called pilot operated or pilot controlled type- One type of diaphragm valve whichhas been employed in the past utilizes a fluid inlet and outlet chamber on the same side of a valve diaphragm, the chambers being in substantially concentric relationship, and in which iiuid is bled from the inlet side through the diaphragm to a third chamber on the opposite side of the valve diaphragm. When iluid is retained Vin this third chamber, the valve diaphragm closes the outlet port or outlet chamber, and the diaphragm is maintained in this closed position by the fluid it:-

self. 'I'he diaphragm is opened by dumping fluid.

from this third chamber into the outlet chamber at a more rapid rate than it can be taken into the third chamber from the inlet chamber. This reverses the pressure balance and causes the valve diaphragm to open. h

In the past. it has been necessary to provide ribs or other spacing' means either on the casing which, together with the valve diaphragm forms the third chamber, or else to provide ribs or spacing means on the diaphragm itself.C

One of the principal features and objects of the present invention ls to provide a novel valve construction in which the necessity for such ribs or spacing means is eliminated, and which provides .a greatly simplified construction.

A further object oi' the present invention is to provide a noveldiaphragm valve which is economical to manufacture-and which is reliable and rugged in use.

A further object of the present invention is to provide a novel valve diaphragm for a pilot operated diaphragm valve.

A still further object of the present invention .is to provide a novel location and arrangement of a bleeder hole in a valve diaphragm of a valve as hereinbefore referred to.

Another and further object of the present invention is to provide a novel combination valve diaphragm and valve casing sealing means or gasket.

Another and still further object of the present invention is to provide a novel method and means for assembling a valve diaphragm in a valve construction.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its manner of construction and method of control together with further objects and advantages, may best be understood by reference to the following description, taken in conjunction with the accompanying drawing,

of being assembled.

'I'he pilot operated diaphragm valve illustrated in the various figures of the drawing includes a casting or housing II having an inlet chamber I2 which is concentric with an outlet chamber I3. The inlet chamber I2 is formed by the outer wall portion I4 of the casting I I and by the valve diaphragm I5. An inlet duct or passageway I6 communicates` with the inlet chamber I2.

The upper edge of the casing wall Il is provided with a shoulder or intumed flange II having an upwardly facing channel or groove I 8 formed therein. Mounted on top of this casting II is a cap member I9 which is bolted or otherwise suitably secured as at to the shoulder I1.

'I'he cap I9 includes a ilange portion 2 I, an intermediate shoulder portion 22 and a long tubular portion 23 which is closed by an end wall 24 at its upper end. The tubular portion 23 is provided with a pilot member 25 which slides freely therein and is formed of some suitable magnetizable -material such as iron or steel. The pilot member 25 has a pointed or tapered lower end 26 which cooperates with the valve diaphragm I5 in a manner presently to be described.

'I'he outlet chamber and passageway of the valve construction includes an inner elbow 2l which is formed as a part of the casting II and which communicates at its lower end with an outlet member 28 which is welded or otherwise suitably secured as at 29 to the casting II. The upstanding portion of the elbow 2l is provided with an interiorly threaded upper end 30 into which a valve seat member 3i is threaded. Below this threaded vportion 30 of the elbow 21 is a shoulder 32 which extends radially outwardly from a double frusto-conical portion 33 leading to the outlet passageway 34- ywhich communicates with the outlet member 2B.

A small clamping ring 35 may be interposed between the flow washer 3e and the valve seat member 3| whereby the valve seat member 3I holds the flow washer 36 in place on the shoulder 32.

The valve seat member 3l includes an upstanding collar portion 31 which provides the Valve seat proper against which the diaphragm i is seated to close off the outlet from the inlet.

The valve diaphragm I5 may be seen best in Figures 2, 3 and 4 of the drawing. This valve diaphragm i5 is preferably formed of rubber or some other suitable resilient material and includes a slightly thickened outer edge 38. an annular exing portion 39 and a reinforced central portion 49. The reinforced central portion 4u h-as a metal insert member 4I which includes a at disk-like base part 42 and a downwardly extending tail portion 43 having a central bore or passageway 44 therein which is contiguous with a bore or passageway 45 in the diaphragm I5. This reinforced central portion 4t of the diaphragm I5 has the base portion 42 of the metal insert 4I embedded therein and is arranged to be seated on the valve seat or collar 31 with the tail portion 43 extending down into the chamber portion I3 formed by the valve seat member 3| above the flow washer 36.

In addition to the central opening 44, 45 in the diaphragm valve I5, there is also provided bleeder hole 46 in the annular portion 39 of the diaphragm I5. It will be observed that the annular portion 39 of the diaphragm I5 is humpshaped in transverse cross-section, and as the diaphragm is raised from its position as shown in Figure 1 of the drawing to its position as shown in Figure 2 of the drawing, the hump-shaped portion unfolds somewhat to enable the reinforced central portion 40 to be raised by locating the bleeder hole 46 slightly inwardly of the top 41 of the hump. When the reinforcedcentral portion 40 is in seated engagement on the valve seat 131 and by properly positioning it from the outer edge of the diaphragm I5, it will be seen that as the hump unfolds and as the central portion 4U rises, the hole moves up until it is exactly at the top of the hump when the diaphragm strikes the shoulder 22 in the cup member I9.

By so doing, all of the uid may be dumped out of the chamber portion 41 which lies above the diaphragm I5 by virtue of the fact that the passageway 44, 45 is substantially greater in cross-sectional area than the bleeder hole 46. It further prevents any uid from being locked in the region between the ange portion 48 of the cap member I9 and the diaphragm I5.

It has always been necessary in the past to provide ribs on either the shoulder 22 or on the diaphragm I5 or some other suitable spacing means to enable all of the fluid above the di aphragm I5 to pass out through the passageway 44, 45, including the portion of uid which would otherwise be trapped between the flange portion 48 of the cap I9 and the diaphragm I5. The need for such spacing means is eliminated entirely by providing a. bleeder hole located in precisely the manner specified above, where it will be noted that in its upper position, the hole lies partly on one side of the top 41 of the hump and partly on the other side. This means that :duid can pass from one side of the hump to the other through the upper portion of the hole, since the upper end of the hole does not lie In a single plane. In other words, due to the fact '4l that there is a crease in the diaphragm through the center of the bleeder hole 46, when the diaphragm I5 is in its upper position, fluid may pass freely from the region between the flange 4-8 of the cap I9 and the diaphragm I5 into the lliarsiber 41 and then out through the passageway As may be seen from' an inspection of Figures 1 and 2 of the drawing, when the pilot member 25 is in its lower position so that the tapered end 26 of the pilot 25 closes the hole 45 in the diaphragm I5, uid under pressure from the inlet I6 will pass through the bleeder hole 46 into the upper chamber 41. Since the fluid under pressure on the upper side of the diaphragm I5 acts over the whole area of the diaphragm, while it only acts over the annular portion 39 on the underside, the fluid pressure itself keeps the diaphragm I5 in its closed position. l If the solenoid 49 which is mounted on the tubular portion 23 is energized, the pilot 25 is lifted up to the top of the tubular portion 23, thus opening the passageway 44, 45. Since this passageway 44, 45 is much larger than the bleeder hole 46, fluid ows out of the chamber 41 faster than it can come in, and the pressure on the upper side of the diaphragm I5 is relieved. The fluid acting against the underside of the diaphragm I5 over the annular portion 39 thus lifts-the diaphragm I5 oi of the valve seat 31 and raises it to the position as shown in Figure 2. Fluid under pressure thus passes freely from the inlet passageway I6 over the valve seat 31 into the chamber I3 and down and out through the outlet member 28.

As hereinbefore indicated, a fiow washer 36 is provided in the outlet passageway on the shoulder 32. This flow washer is made of rubber or other suitable resilient material and is provided with an opening 50 therein. The opening 53 is substantially smaller in diameter than the diameter of the inner edge of the shoulder 32 so that the flow washer 36 flexes under fluid pressure in the manner shown in Figure 2, thus reducing the size of the orifice opening in the flow washer 36 through which the fluid passes. The greater the pressure, the smaller will be the cross-sectional opening of the upper end of the hole 50 in the washer 36.y

It has been found that by properly proportioning the relative size of the opening 50 with respect to the inner edge of the shoulder 32 substantially uniform now rate may be maintained over a widel range of fluid pressures.

As will be seen best in Figures 2 and 4 of the .1

drawing, the valve diaphragm serves not only as the valve memberbut also as a gasket for making.- a fluid-tight seal between the cap I9 and thel housing or casting II. The outer enlarged marginal portion 38 of the diaphragm I5 makes an interlocking seated engagement in the annular While I have shown a particular embodimentof my invention, it will, of course, be understood that I do not wish to be limited thereto, since many modications may be made, and I, therefore, contemplate by the appended claims to cover all such modifications that fall within the true spirit and scope of my invention.

' section and having a bleeder hole in said hump,

so arranged that it will be spaced radially inwardly of the top of the said hump when said diaphragm is in a normal unstressed condition and will move outwardly to exactly the top of said hump when said diaphragm is at its maximum extended stressed condition.

2. A valve including a valve diaphragm having a relatively still central portion, a flexible annular portion surrounding said central portion and an outer portion, means for securing and hoding said outer portion to support said diaphragm in operating position within said valve including a valve casing forming a chamber on one side of saidy diaphragm and a cap member closing and forming a chamber on the opposite side of said diaphragm, said flexible portion of said diaphragm having aA hump therein in transverse section and seating against the inside wall ofosaid cap member when said diaphragm is in -an extended position, and having a bleeder hole in said hump so arranged that it will be located inwardly of the top of said hump when said diaphragm is in a closed position and will move to exactly the top of said hump. when said diaphragm is in its maximum open position.

6 f sition and will move outwardly to exactly the top of said hump when said diaphragm is in its maximum open position, said central portion having an orifice therethrough, and a pilot movable to open and close said orice.

4. A fluid control unit for controlling the passage of fluid therethrough comprising a housing, a flexible diaphragm extending across the interior of said housing and dividing said housing into a first and a second chamber, said housing having a fluid inlet duct communicating with said first chamber, an outlet pipe extending from the wall of said housing and projecting into said first chamber, the inner end of said pipe being disposed in close proximity to a central portion of said diaphragm and arranged to be closed off by the same, said second chamber having a wall portion against which the diaphragm seats when in an extended position, said diaphragm having al flexible region surrounding said central portion, said flexible region having a hump therein in transverse section and a bleeder hole in said hump so arranged that it will be located inwardly of the top of said hump when said diaphragm is heated against the inner end of said pipe and will move outwardly to the top of said hump when said diaphragm is in its extended position and said hump is seated against a wall portion of said second chamber, said bleeder hole forming a communicating passage between said rst and second chambers, said diaphragm having an opening through its central portion over the end of said 3. A valve including a valve diaphragm having a relativelystii central portion, a flexible annular portion surrounding said central. portion and an outer portion, means for securing and holding said outer portion to support said diaphragm in operating position within said valve including a cap member closing the top of said diaphragm, said flexible portion of said diaphragm having a hump therein in transverse section and seating against an inner wall portion of said cap member when said diaphragm is in an extended position, and said diaphragm having a bleeder hole inv said hump, said bleeder hole being so arranged that it will be located radially inwardly of the top of said hump when said diaphragm is in a closed popipe, and means for opening and closing said center opening in said diaphragm to control opening and closing of the 'end of said pipe by said diaphragm.

^ LESLIE A. KEMPTON.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS 

